This invention generally relates to apparatus for treating waste water and, more particularly, to apparatus for treating used emulsions and industrial waste waters which has a rectangular, box-like shape with a reaction container in which the fluid to be treated is mixed with a chemical mixture; a settling container in contact with the same in which the forming precipitate separates and settles from the fluid; as well as devices for discharging or transporting the precipitate from the settling container, and devices for dividing the chemical mixture among the fluids to be treated.
German disclosure document No. 31 24 738 describes an apparatus for treating used emulsions and industrial waste waters. In that apparatus, the precipitate is discharged from the settling container by means of a honeycomb band and released on an oblique surface from which it finally flows into a basin in a band filter. The precipitate, which is transported away in this manner from the settling container, still contains abundant water, so that it can flow away on this obliquely inclined surface.
On the band filter, which is a water-permeable cellulose or fibrous structure, the precipitate loses a portion of its water before finally flowing to a special device in which the band filter travels through pressure rollers which remove additional water. Such apparatus is bulky and expensive and requires a great deal of space and, because of the band filter and the pressure rollers, also entails considerable investment and maintenance costs. Furthermore, the flowing waste water necessitates a storage device extending over practically the entire lower area and a separate pipeline is required for the transport of the waste water.
It is the task of the present invention to provide an apparatus of the aforementioned type which, however, is compact, in which the reaction container, the settling container and other parts accommodating the waste water are sealed so that even during tilting tipping and swinging motions, no fluids spill, such as, for example, if the device is installed onboard a ship, and which has a simple, easy to monitor, maintenance-free construction.
In accordance with the invention, this task is solved through the fact that the containers which accommodate the fluids are box-shaped with straight walls. The precipitate in the settling container is discharged therefrom by means of a honeycomb band which slides with its external surfaces between opposing sidewalls and above the base so as to exit the container through slots which are dimensioned to correspond to the cross-section of the honeycomb band. The precipitate proceeds through the slots to the outside of the container above the precipitate storage tank.
The honeycomb band, which has a width corresponding to that of the settling container, follows a rectangular path over three guide rollers and one drive roller. Two of the guide rollers for the honeycomb band lie in the opposing corners formed by the intersection of the sidewalls and the base, while the third guide roller lies vertically above one of the lower rollers. The drive roller is positioned vertically above the other lower roller.
A channel-like guide for the honeycomb band is formed between each vertically-standing sidewall and an additional inner sidewall which is positioned parallel to each sidewall at a distance therefrom which is slightly greate than the thickness of the honeycomb band. The honeycomb band is an endless band and consists of two horizontal portions which lie opposite one another and two likewise opposed vertical portions.
The honeycomb band thus forms a rectangular loop which extends far enough over the container, which accommodates the fluid between the vertical endpieces of the honeycomb band, so that a storage container for the precipitate can be inserted to receive the precipitate falling from the upper horizontal endpiece. The emptying of the honeycomb band in the upper horizontal endpiece is achieved by the use of a tapping device, which rhythmically strikes against the upper horizontal surface of the honeycomb band.
The honeycomb band is driven by an electric motor with a regulating gear unit. A drive roller, preferably having two toothed rims, is provided wherein the rims engage two corresponding honeycomb unit rows of the honeycomb band in order to drive the honeycomb band.
The honeycomb band moves, corresponding to the formation of the precipitate, relatively slowly over the base of the settling container so that the precipitate that flakes and precipitates out of the fluid settles onto the honeycomb band and, during the motion of the honeycomb band, is moved therewith and transported upward out of the settling container.
As the precipitate in the honeycomb band moves upward outside the settling container, it dehydrates because of the long residence time to such a degree that a compression device or the like is not necessary, as it is in the prior apparatus.
The apparatus is provided with inlet and outlet pipes through which the waste water to be treated can be let in and the treated waste water can be discharged, respectively. In this manner, a practically continuous operation is possible with the apparatus of the present invention.
The fluid exiting from the apparatus is clarified to such a degree that it can be directed to a preliminary channel or can also, if the device is installed on a ship, be directed to a corresponding space in the double base which can then be emptied during the next harbor stay.
The receiver container can be a basin which is capable of tipping so that the sediment or precipitate settling out can be emptied directly into disposable packages or plastic sacks. Instead of the tipping basin, other devices for the removal of the precipitate settling out of the honeycomb band are conceivable, such as, for example, a basin which is V-shaped in cross-section whereby the sidewalls of this V shaped basin are inclined to the vertically-standing endpiece of the honeycomb bands which lie opposite one another. This basin has a circular cross-section base and contains a conveying unit which feeds the precipitate into a tube which is connected with a receiving container.
The box containing the reaction and settling containers is sealed at the top by means of a plate and has only slot shaped openings through which the honeycomb band passes. The honeycomb band emerges upwardly from the container passing through the slot shaped opening and, reenters the container by passing through another slot-shaped opening on the opposite side of the container after it has covered a U-shaped path above the surface of the container.
Thus, the contents of the settling container are sealed so that fluid can not escape during tipping.